It happened on the B3081 near Verwood - he had to be cut free by firefighters.
More Volunteers For Dorset Police?
Dorset’s Police and Crime Commissioner Martyn Underhill and the Force have thanked the hundreds of police volunteers who give up their free time to support their local communities.
Dorset PCC Martyn Underhill said:
"Volunteers are the life blood of Dorset Police. They are helping to make Dorset safer for everyone who lives, works and visits the county.
"They have brought energy and passion to the streets of Dorset and are helping to improve relationships with the communities we serve. I want to thank them for their service to Dorset Police and to the people of Dorset.
"I am immensely proud of their contribution to the Force and to Dorset. Their time, experience and dedication is hugely valued."
Dorset Police is running its Countdown to Christmas campaign, which aims to remind residents how to avoid becoming a victim of crime during the festive season and highlight the great work which takes place within the Force.
Inspector Mike Darkin, Volunteers Team Leader, said:
"I remain humbled and entirely grateful for the valuable support offered by each and every one of our volunteers.
"Over 47,000 hours of formal voluntary service to Dorset Police has been logged in 2013 by our team of special constables and formal volunteers, who collectively total 366 at this time.
"Add to this the many more hours given freely by our ever-widening support volunteer family and a truly incredible picture begins to develop. I look forward to 2014 and to further developing our ever-growing voluntary workforce, thereby ensuring that Dorset remains a safe and welcoming place for people to live, work and visit.
"To each and every special constable and volunteer, I offer my sincere thanks for your continued valuable support and my very best wishes to you and your families for the festive season."
There are currently 151 active volunteers working for Dorset Police in a variety of roles and areas of the Force, including CCTV operators, community messaging and administration support.
Dorset PCC Martyn Underhill has pledged to significantly increase the number of volunteers in his term of office.
For more information about becoming a volunteer and the latest volunteer vacancies visit dorset.police.uk.
You can follow the Countdown to Christmas campaign on Twitter @dorsetpolice and looking out for #DPXmasCountdown.
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